Light Dimmer Nonfunctional

spielnicht · 11-17-2023, 08:22 AM

Just noticed my dimmer wheel on the light switch isn't working. is this a common fault? They're not cheap as new, so wondering if buying a used one will have the same issue.

JAS1169 · 11-17-2023, 01:56 PM

I'm not a computer person & I'm not sure if the Z4 E85 can be affected by this but, some BMW's can have a milage tamper dot caused when a new or used LCM is installed.

Please see: https://www.bing.com/videos/rivervie...F457&FORM=VIRE

You know, if it was me, I'd simply try giving the wheel area of the dimmer a good cleaning with a spray can of Electrical Contact Cleaner. It really sounds like the contacts are either gummed up or tarnished.

KevinC · 11-17-2023, 10:44 PM

Mine failed when the car was almost new back in 2007 and was replaced under warranty.

A new LCM (light switch contains the entire light control module) is big bucks - like $400 new. I'm pretty sure it doesn't need to be coded because I replaced the switch in my 2nd Z4M when I was having panel dimming issues, and it worked fine without coding.

I like the contact cleaner suggestion above. Good luck!

spielnicht · 11-20-2023, 07:34 AM

That explains then the high cost. Will try the contact cleaner suggestion first and go from there. Thank you.

11-17-2023, 08:22 AM	#1
spielnicht Petrolhead 440 Rep 808 Posts Drives: 24 X3 M40i/14 550i/08 Z4 3.0si Join Date: Apr 2017 Location: Virginia iTrader: (3) Garage List 2008 BMW Z4 3.0si [9.67] 2014 BMW 550i [6.00] 2024 BMW X3 M40i [9.25]	Light Dimmer Nonfunctional Just noticed my dimmer wheel on the light switch isn't working. is this a common fault? They're not cheap as new, so wondering if buying a used one will have the same issue. __________________ . 2024 X3 M40i 2014 550i 2008 Z4 3.0si 6MT 2011 Z4 35si (sold)
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11-17-2023, 01:56 PM	#2
JAS1169 Private First Class 50 Rep 156 Posts Drives: BMW 2003 Z4 Join Date: Sep 2017 Location: Mechanicsburg, PA iTrader: (0)	I'm not a computer person & I'm not sure if the Z4 E85 can be affected by this but, some BMW's can have a milage tamper dot caused when a new or used LCM is installed. Please see: https://www.bing.com/videos/rivervie...F457&FORM=VIRE You know, if it was me, I'd simply try giving the wheel area of the dimmer a good cleaning with a spray can of Electrical Contact Cleaner. It really sounds like the contacts are either gummed up or tarnished.
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11-17-2023, 10:44 PM	#3
KevinC your average JAMF 3101 Rep 4,094 Posts Drives: '21 M2 Comp, '19 Golf R Join Date: Oct 2005 Location: Cochise County, AZ iTrader: (0) Garage List 2019 VW Golf R [0.00] 2021 BMW M2 Competi ... [0.00]	Mine failed when the car was almost new back in 2007 and was replaced under warranty. A new LCM (light switch contains the entire light control module) is big bucks - like $400 new. I'm pretty sure it doesn't need to be coded because I replaced the switch in my 2nd Z4M when I was having panel dimming issues, and it worked fine without coding. I like the contact cleaner suggestion above. Good luck! __________________ '21 M2 Comp '19 Golf R
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11-20-2023, 07:34 AM	#4
spielnicht Petrolhead 440 Rep 808 Posts Drives: 24 X3 M40i/14 550i/08 Z4 3.0si Join Date: Apr 2017 Location: Virginia iTrader: (3) Garage List 2008 BMW Z4 3.0si [9.67] 2014 BMW 550i [6.00] 2024 BMW X3 M40i [9.25]	That explains then the high cost. Will try the contact cleaner suggestion first and go from there. Thank you. __________________ . 2024 X3 M40i 2014 550i 2008 Z4 3.0si 6MT 2011 Z4 35si (sold)
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